Decrease In Velocity Research Articles

Unsteady nanofluid flow over a cone featuring mixed convection and variable viscosity

This article addresses unsteady nanofluid flow over a cone with MHD and mixed convection effects. Effects of variable viscosity and viscous dissipation are also considered. The resulting system of equations is tackled through the Homotopy Analysis Method (HAM). The impact of different influential variables on skin friction coefficient, heat and mass flux are discovered through numerical tables and graphs. It is noted that the surface drag force in x and y directions increases against the buoyancy force parameter. Also, it is observed that the tangential and azimuthal velocity decrease against the variable viscosity parameter. Furthermore, the temperature of fluid is observed to decay against the unsteady parameter but it increases against the Eckert number.

Efficiency of the transcranial magnetic stimulation in the treatment 
 of occupational polyneuropathy

Introduction. In occupational polyneuropathies, along with sensory and autonomic disorders, excessive sensory input can lead to the development of excitation foci in various parts of the central nervous system, clinical significance of which is currently insufficiently studied.
 The aim of the study was the evaluation of the clinical effects of the transcranial magnetic stimulation in the dorsolateral zone of the prefrontal cortex in mine workers with occupational polyneuropathy. 
 Materials and methods. There were examined thirty six workers of coal mining enterprises of Kuzbass with a proven diagnosis of polyneuropathy of the upper extremities, the average age was 50.2±3.7 years, and the average work experience was 23.4±3.5 years. To confirm polyneuropathy, the parameters of sensory conduction along the nerves of the upper extremities were investigated using electroneuromyography, nerve conduction velocity along the median and ulnar nerves was determined. The assessment of autonomic rcontrol was carried out using spectral analysis of heart rate variability. The functional brain status was determined by an electroencephalogram.
 Results. The patients complained of pain in the extremities, numbness and paresthesia. According to electroneuromyography, there was a decrease in the nerve conduction velocity along the somatic sensory nerves of the upper extremities, a reduction in the power of oscillations in all frequency ranges of the heart rate variability spectrum, which was more pronounced in the high frequency range. Transcranial magnetic stimulation of the prefrontal cortex zone of the right hemisphere was performed with a stimulus with a frequency of 1 Hz for 5 min, over a course of 5 procedures, after which a statistically significant increase in the average nerve conduction velocity along the somatic sensory nerves of the upper extremities, and a rise in the spectral parameters of the heart rate variability were observed. An increase in the alpha rhythm index at the electroencephalogram indicated an amplification of the integrative brain activity, which provided a wide range of regulatory processes. The patients noted a decrease in the intensity of pain, the severity of sensitive disorders, and improvement in general well-being.
 Limitations. The study is limited to the number of mine workers with a proven diagnosis of upper extremity polyneuropathy, without cardiac arrhythmias, structural damage and metal implants in the brain.
 Conclusion. Transcranial magnetic stimulation of the dorsolateral zone of the prefrontal cortex is effective in correcting sensory and autonomic disorders in occupationally caused polyneuropathy by activating suprasegmentary autonomic centers involved in systemic adaptation processes. It is promising to further expand the list of stimulation targets and create effective protocols for the use of transcranial magnetic stimulation.

Cardio-protective effect of trimetazidine in patients with disseminated breast cancer

Abstract Funding Acknowledgements Type of funding sources: None. Relevance of the problem. Anthracycline cardiotoxicity is the most unfavorable form due to irreversible complications of cardiovascular system caused by anthracyclines during the chemotherapy (CT) of the breast cancer (BC). Despite the fact that this type of cardiotoxicity has been studied better than others, the problem of preventing such complications remains relevant to this day. In our study, we suggest Trimetadizine (TMZ) as a cardioprotective agent in patients with disseminated breast cancer receiving Doxorubicin chemotherapy. Material and methods The study included 93 patients (aged 41.2±8.3 years) who underwent surgery for breast cancer and several courses of chemotherapy with Doxorubicin (according to the stage of breast cancer). Patients were randomized into 2 groups: the first group (n=47; G1) received TMZ at a dose of 70 mg daily, in the control group (n=46; G2) patients didn't receive TMZ. All patients before the start of the study underwent a complete echocardiographic examination and checked cardiac biomarkers such as troponin and brain natriuretic peptide (BNP). The exclusion criterion was patients with any kind of cardiovascular pathology. The primary endpoint of the study was a reduction in left ventricular ejection fraction (LVEF) deterioration as assessed by series of echocardiographic studies conducted after each course of chemotherapy, and then every 3 months after completion of chemotherapy for 1 year. Secondary outcome measures included echocardiographic (EchoCG) measurements of LV diastolic dysfunction, structural myocardial changes assessed by echocardiography, and control cardiac biomarkers. Results Both groups achieved the same cumulative dose of Doxorubicin. No patient died or discontinued chemotherapy during the study. There were no significant differences between the two groups in terms of baseline clinical findings, echocardiographic parameters, and changes in biomarkers. 3-5 months after the start of CT, standard echocardiography showed unreliable changes in LVEF, shortening fraction, and LV measurements. However, tissue Doppler showed a decrease in myocardial velocity (P = 0.001) in G2, indicating LV diastolic dysfunction. While no such changes were observed in G1. Conclusion Tissue Doppler proved to be more sensitive than standard echocardiography for early diagnosis of cardiac dysfunction, and TMZ appears to have a cardioprotective effect in case of anthracycline cardiotoxicity.

Numerical study on the flow and heat transfer of molten salt in a horizontal pipe applied transverse magnetic field

Based on a modification of a magnetohydrodynamic turbulence model, a numerical study was performed to investigate the effects of transverse uniform and gradient magnetic field on the turbulent flow and heat transfer characteristics of a low melting point molten salt in a stainless steel pipe. With the Hartmann number from 0 to 80, the numerical results showed that the fluid flow displayed anisotropic distributions under the magnetic field with decrease of velocity in the mainstream region, and decrease of turbulent intensity, whereas the flow velocity increased in the boundary layer near the Hartmann and Roberts wall. Especially, a velocity jet phenomenon was observed in the Roberts boundary layers at higher Hartmann number in the uniform magnetic field or the positive gradient magnetic field. Under the gradient magnetic field, the flow and heat transfer of molten salt displayed much more variations than under the uniform magnetic field. The magnetohydrodynamic calculation results proposed here might be helpful to the design of the composite heat transfer system for molten salt in actual industrial applications.

Continuous monitoring of cerebral blood flow during general anaesthesia in infants

BackgroundGeneral anaesthesia is associated with neurocognitive deficits in infants after noncardiac surgery. Disturbances in cerebral perfusion as a result of systemic hypotension and impaired autoregulation may be a potential cause. Our aim was to study cerebral blood flow (CBF) velocity continuously during general anaesthesia in infants undergoing noncardiac surgery and compare variations in CBF velocity with simultaneously measured near-infrared spectroscopy (NIRS), blood pressure, and heart rate. MethodsNeoDoppler, a recently developed ultrasound system, was used to monitor CBF velocity via the anterior fontanelle during induction and maintenance of general anaesthesia until the start of surgery, and during recovery. NIRS, blood pressure, and heart rate were monitored simultaneously and synchronised with the NeoDoppler measurements. ResultsThirty infants, with a median postmenstrual age at surgery of 37.6 weeks (range 28.6–60.0) were included. Compared with baseline, the trend curves showed a decrease in CBF velocity during induction and maintenance of anaesthesia and returned to baseline values during recovery. End-diastolic velocity decreased in all infants during anaesthesia, on average by 59%, whereas peak systolic- and time-averaged velocities decreased by 26% and 45%, respectively. In comparison, the reduction in mean arterial pressure was only 20%. NIRS values were high and remained stable. When adjusting for mean arterial pressure, the significant decrease in end-diastolic velocity persisted, whereas there was only a small reduction in peak systolic velocity. ConclusionsContinuous monitoring of CBF velocity using NeoDoppler during anaesthesia is feasible and may provide valuable information about cerebral perfusion contributing to a more targeted haemodynamic management in anaesthetised infants.

Measurements of particle velocity and solid concentration near the wall of a cyclone using high-speed particle shadow velocimetry

The particle velocity and solid concentration distribution in the near-wall region of a cyclone separator was experimentally studied. A series of measurement experiments were conducted based on the high-speed particle shadow velocimetry (HPSV) method. The experiment was conducted on a ϕ160 mm cyclone at an inlet velocity of 12-20 m/s and inlet concentration of 30-300 g/m3 with glass beads whose median diameter was 136.7 μm. The measured results of the microscopic particle movement demonstrate the moving behavior of the spiral particle band near the cyclone wall. It was found that the particle velocity and solid concentration are greatly different from those in and outside the particle band. The particle velocity inside the particle band can drop to 1.9 m/s, while the dispersed particle velocity outside the particle band away from the wall can reach 15.2 m/s. Along the downward movement of particle band, the particle velocity decrease and velocity fluctuation become milder, the solid concentration increases four times and reaches the highest at the cone wall. On the cross-section plane, the solid concentration decreases along the radial direction away from the wall. In the near-wall region inside particle band, the solid concentration can reach 0.004 or even higher, which is 32 times higher than the inlet solid concentration. This study helps to understand the complex gas-solid two-phase flow phenomena in cyclones.

Analytical Model of Transpired-Coolant Concentration at Downstream Wall in High-Speed Laminar Flow

An analytical model based on one-dimensional diffusion is proposed to predict the mixing between the coolant gas and the boundary-layer gas at the wall downstream of a transpiring injector in a laminar flow. The model is validated against coolant concentration data experimentally obtained at Mach 7 over a flat plate at a zero pressure gradient. It successfully predicts the mixing at the wall downstream within 17% of the experimental data. It is shown that this mixing mechanism at the wall in laminar flows is fully described by the process of diffusion. The coolant coverage at a given downstream location is promoted when the streamwise velocity decreases, the blowing ratio increases, or the diffusion coefficient drops. Finally, a mass budget calculation is performed for a transpiration-cooled hypersonic vehicle employing the analytical model. The model predicts a mass requirement of 3.6 times less coolant when helium is used as the coolant gas as opposed to nitrogen for the chosen trajectory. However, helium requires twice the storage volume as compared to nitrogen.

Thermal control performance evaluation of a phase change material-based heat sink for the electronic device suffering transient heat flux shock

To solve the instantaneous thermal shock of electronic devices suffering transient heat flux, a phase change material-based heat sink is designed. The thermal control performance on the maximum temperature, phase change material liquid volume fraction, energy storage rate of the phase change material, natural convection heat transfer between the system and surrounding air, and temperature control efficiency is studied. Results show that in comparison to the heat sink without phase change material, the maximum temperature of the phase change material-based heat sink can be reduced by approximately 10 K. When the phase change material is filling outside the fins, optimum thermal performance can be achieved. For these three PCM and fin combinations, an outstanding temperature control efficiency can be achieved by the fin outside filling scheme, which is about 19%. The temperature control ability is restrained as the electrical device is situated at an angle with a vertical direction. As the orientation increases from 0° to 30°, 60°, and 90°, the average flow velocity decreases by 7.12%, 50.6%, and 75.7%, respectively. In addition, when the dimensionless phase change material filling size is 0.3, a relatively excellent heat transfer performance can be achieved.

Thermal Characteristics of an Unsteady Hybrid Nano-Casson Fluid Passing Through a Stretching Thin-Film with Mass Transition

In current communication, the thin-film flow of Casson hybrid nanofluid consists of copper and alumina nanoparticles that dissolved in carboxymethyl cellulose (CMC) plus water over an unsteady stretching porous sheet is elucidated. Using suitable similarity variables, the resultant partial governing equations are turned into a set of nonlinear ordinary differential equations. The Keller box approach is then used to solve the transformed equations. The unknown thin-film thickness constant is determined by using the homotopy analysis approach. The thermal and velocity distributions, as well as the Nusselt number and skin friction of the fluid, are discussed for different values of relevant parameters such as thin-film thickness, nanoparticles volume fraction, and mass transition parameter. The distributions of temperature and velocity decrease when the thin-film thickness is increased. The velocity distribution is decreased by the Casson, nanoparticles volume fraction, and mass transition (injection) parameter. The temperature is enhanced by the nanoparticle's volume fraction and the Casson parameter, however, has an opposite tendency with the mass transition (injection) parameter. For the physical quantities, the skin friction has a negative function with all the parameters. The mass transition (injection) parameter increases the Nusselt number. The outcomes of the present study are useful for example in producing the smart contact lens that has been used in the biomedical field.

A Novel Quantitative Electrocardiography Strategy Reveals the Electroinhibitory Effect of Tamoxifen on the Mouse Heart.

Tamoxifen, a selective estrogen receptor modulator, was initially used to treat cancer in women and more recently to induce conditional gene editing in rodent hearts. However, little is known about the baseline biological effects of tamoxifen on the myocardium. In order to clarify the short-term effects of tamoxifen on cardiac electrophysiology of myocardium, we applied a single-chest-lead quantitative method and analyzed the short-term electrocardiographic phenotypes induced by tamoxifen in the heart of adult female mice. We found that tamoxifen prolonged the PP interval and caused a decreased heartbeat, and further induced atrioventricular block by gradually prolonging the PR interval. Further correlation analysis suggested that tamoxifen had a synergistic and dose-independent inhibition on the time course of the PP interval and PR interval. This prolongation of the critical time course may represent a tamoxifen-specific ECG excitatory-inhibitory mechanism, leading to a reduction in the number of supraventricular action potentials and thus bradycardia. Segmental reconstructions showed that tamoxifen induced a decrease in the conduction velocity of action potentials throughout the atria and parts of the ventricles, resulting in a flattening of the P wave and R wave. In addition, we detected the previously reported prolongation of the QT interval, which may be due to a prolonged duration of the ventricular repolarizing T wave rather than the depolarizing QRS complex. Our study highlights that tamoxifen can produce patterning alternations in the cardiac conduction system, including the formation of inhibitory electrical signals with reduced conduction velocity, implying its involvement in the regulation of myocardial ion transport and the mediation of arrhythmias. A Novel Quantitative Electrocardiography Strategy Reveals the Electroinhibitory Effect of Tamoxifen on the Mouse Heart（Figure 9）. A working model of tamoxifen producing acute electrical disturbances in the myocardium. SN, sinus node; AVN, atrioventricular node; RA, right atrium; LA, left atrium; RV, right ventricle; LV, left ventricle.

Positive Ion Critical Velocity for Nucleation of Quantized Vortices in Isotopically Pure ^4He

The critical velocity for the vortex nucleation of positive ions is determined experimentally in isotopically purified ^4He at temperatures as low as 50 mK. Systematic IV characteristic measurements for a two-dimensional positive ion pool at a depth of 37.6 nm from the surface are carried out with extremely fine control of driving electric fields. The critical velocity of {sim }32 ms^{-1} at 500 mK decreases with decrease in temperature and approaches a temperature-independent value of {sim }18 ms^{-1} below 200 mK. The decrease in critical velocity corresponds to the increase in nucleation rate. The temperature dependence of critical velocity is qualitatively attributed to the “superohmic” macroscopic quantum tunneling of the Caldeira–Leggett theory. The reduction in tunneling rate with increase in temperature is evidence for quantum friction.

Multi-objective optimization of aerodynamic and erosion resistance performances of a high-pressure turbine

Focusing on a high-pressure turbine, this study conducts a multi-objective optimization aimed to improve its aerodynamic and erosion resistance performances. With a self-adaptive updated Kriging model first applied, the Latin hypercube sampling method and NSGA-II algorithm are then used to find trade-off solutions. The sensitivity analysis shows that the efficiency is mainly influenced by the flow angles near trailing edges of three selected blade spans, among which the flow angle near the trailing edge of middle span is the most significant, followed by the root span and tip span, while the dominant design parameters affecting the erosion are the flow angles near trailing edges of middle span and tip span. After optimization, the erosion around the middle span on pressure side and middle chord on suction side is significantly reduced due to the decrease of impact velocity and impact frequency, and the increase of impact angle. Besides, the low-velocity fluid regions near the pressure side of middle span and the trialing edge of tip are greatly reduced, which can relieve the blockage of flow passage. At all axial sections considered, the optimized blade is shown to significantly reduce losses near the tip and suction side, especially at 80% axial section.

Deviations from spherical shape decrease the growth velocity in granular aggregate collisions – a granular mechanics study

ABSTRACT We used granular mechanics simulations to study collisions between spherical aggregates and axisymmetric ellipsoidal aggregates of equal mass. Non-spherical aggregates may be generated, for example, as the result of previous aggregate collisions, either from the merging of aggregates or from fragmentation processes. Of particular interest is the growth velocity, i.e. the critical collision velocity above which the size of the largest post-collision fragment is smaller than the original aggregate size. We find a systematic decrease of the growth velocity with axis ratio of the ellipsoid. The decrease is caused by the ‘rim peel-off’ effect: grain material close to the rims is more readily ejected from the boundaries of aggregates. When considering collisions with ellipsoids of identical semimajor axis, the growth velocity of oblate ellipsoids surpasses that of prolate ellipsoids. Averaging over the orientation of the ellipsoid and over the impact parameters possible in a collision retains the above-mentioned results. The influence of aggregate shape on collision outcomes is of interest, for instance, for codes describing the evolution of dust clouds under collisions.

The lunar solid inner core and the mantle overturn.

Seismological models from Apollo missions provided the first records of the Moon inner structure with a decrease in seismicwave velocities at the core-mantle boundary1-3. The resolution of these records prevents a strict detection of a putative lunar solid inner core and the impact of the lunar mantle overturn in the lowest part of the Moon is still discussed4-7. Here we combine geophysical and geodesic constraints from Monte Carlo exploration and thermodynamical simulations for different Moon internal structures toshow that only models with a lowviscosity zone enriched in ilmenite and an inner core present densities deduced from thermodynamic constraints compatible with densities deduced from tidal deformations. We thus obtain strong indications in favour of the lunar mantle overturn scenario and, in this context, demonstrate the existence of the lunar inner core with a radius of 258 ± 40 km and density 7,822 ± 1,615 kg m-3. Our results question the evolution of the Moon magnetic field thanks to its demonstration of the existence of the inner core and support a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System8.

Experimental study on the role of clay mineral and water saturation in ultrasonic P-wave behaviours across individual filled rock joints

Understanding wave propagation across rock joints is of great importance in rock engineering, petroleum engineering, and other geophysical applications. Previous studies have shown that wave behaviours across filled rock joints are highly affected by the properties of filling materials. However, how clay minerals and water saturation of the infilling affect wave attributes across filled rock joints is still poorly understood. In this study, ultrasonic tests were conducted on kaolinite- and bentonite-filled rock joints to investigate the roles of clay minerals and the water saturation of infillings on elastic P-wave behaviours across individual filled rock joints. The test results show that the infilling's water saturation and mineralogical compositions have combined effects on P-wave signatures of single rock joints filled with clayey soils. Particularly, for the kaolinite-filled rock joint, P-wave velocity and attenuation first increase and then slightly decline with the increasing water saturation. By contrast, for the bentonite-filled rock joint, an increase in water saturation causes gradual decreases in velocity and attenuation. The integrated interpretation of the experimental results indicates that the difference in heterogeneity saturation due to clay hydration is the first-order reason for the discrepancies in saturation-dependent P-wave attributes between kaolinite- and bentonite-filled rock joints. The findings of this study can help further understand wave propagation and attenuation across rock joints filled with fluid-saturated clayey soils.

Ab initio lattice thermal conductivity of (Mg,Fe)O ferropericlase at the Earth’s lower mantle pressure and temperature

The effects of iron (Fe) incorporation on the lattice thermal conductivity () of MgO are investigated under the Earth’s lower mantle pressure (P) and temperature (T) condition (P > ∼20 GPa, T > ∼2000 K) based on the density-functional theory combined with the anharmonic lattice dynamics theory. The of ferropericlase (FP) is determined combining the internally consistent LDA + U method and self-consistent approach to solve the phonon Boltzmann transport equation. The calculated are well fitted to the extended Slack model which is proposed in this study to represent in a wide volume and T range. Results demonstrate that the of MgO decreases strongly by Fe incorporation. This strong negative effect is found due to decreases in phonon group velocity and lifetime. Consequently, the of MgO at the core-mantle boundary condition (P∼ 136 GPa, T ∼ 4000 K) is substantially reduced from ∼40 to ∼10 W m−1 K−1 by the incorporation of Fe (12.5 mol%). The effect of Fe incorporation on the of MgO is found to be insensitive to P and T, and at high T, the of FP obeys a well-established T inverse relation unlike the experimental observations.

Quantification of seismic performance index limits and evaluation of seismic fragility for a new rectangular prefabricated subway station structure

To promote the acceptance of prefabricated technology in underground engineering, the numerical seismic fragility analysis of a prefabricated underground structures was scrutinized. A method to quantify the limit values of the seismic performance index of rectangular prefabricated subway station structure was proposed. In addition, seismic fragility curves of the two-story three-span prefabricated subway station structure were constructed based on peak ground velocity (PGV) and peak ground acceleration (PGA), which can be used as an effective tool to quickly evaluate the seismic performance of this type of prefabricated underground structure, and compared with the cast-in-place subway station structure. The results demonstrate that the ground motion and site class have an intertwined influence on the dynamic response of the underground structures. That is, as the site equivalent shear wave velocity decreases, the ground motion characteristics have a greater influence on the underground structure dynamic response and its susceptibility to damage. For shallow buried multi-layer underground prefabricated structures, the PGV is the best seismic intensity measure (IM) for all site classes. The prefabricated subway station structure is found to be less vulnerable to damage than the cast-in-place subway station structure.

Characterization Nanoparticles via Newtonian Heating for Fractionalized Hybrid Nanofluid in a Channel Flow

The characterization or measurement of the physical and chemical properties of nanoparticles usually lies in the field of nanometrology based on the different characterization techniques. In order to boost the rate of heat transmission, in this regard, an unsteady and convection flow of a fractionalized hybrid nanofluid in a vertical microchannel consisting of two parallel plates apart is studied through Newtonian heating. The governing equations are fractionalized based on the Caputo–Fabrizio derivative of the non-singular and as an exponential kernel. The fractionalized governing equations are solved by utilizing the Laplace approach. For the Laplace inversions, the Zakian algorithm is utilized to acquire the semi-analytical solution. The obtained solutions are also compared with Stehfest and Tzou numerical algorithms to check the validity. For understanding the physics of the under-considered problem, Mathcad software is used for numerical results and graphical representations. The impacts of different physical parameters are deliberated and exhibited in figures. The Prandtl number Pr always shows a decreasing trend for the temperature and velocity profile. Velocity decreases by growing φ due to increasing the viscosity of nanofluid with φ. The thermal conductivity is improved by increasing φ, so that temperature distribution is increased. This study has numerous applications in thermal engineering.

Effects of different physical properties of anthracite powder fuel on detonation characteristics of a rotating detonation engine

The rotating detonation engine (RDE) fueled by coal powder has attracted much attention because of its high thermal cycle efficiency. To explore the detonation characteristics of anthracite powder and further study the effects of particle size and morphology on them, a series of rotating detonation experiments with anthracite powder were carried out in a disk-shaped combustor. The experimental results show that the morphology of anthracite particles plays an important role in detonation. The addition of porous anthracite (PA) enhances the detonation intensity in the lean hydrogen–air, while flaky anthracite (FA) weakens it. The concentration rise of PA increases the detonation wave height, while FA does not have such an obvious effect on the height. The excessive addition of any anthracite powder increases the heat loss of the detonation, resulting in a decrease in detonation velocity. By comparing the detonation characteristics of 20-nm, 3-μm, and 40-μm PA, it is found that the detonation performance of 20-nm PA, which has strong agglomeration, has no significant advantages over the micron-sized PA. Among the three PA powders, 3-μm PA has the largest detonation intensity and velocity. The difference in engine performance caused by pulverized anthracite with different morphological characteristics is as follows: when the mass flow rates of coal, H2, and air are 6.7, 5.3, and 260 g/s, respectively, the specific impulse of 3-μm PA reaches 7.8 kN·s/kg, which is about 2.7 times higher than that of 5-μm FA. This research provides theoretical guidance for the powder fuel selection of the RDE.

Electrophysiological assessment of patients recovered from COVID-19 infection

Background: Neurological manifestation associated with Coronavirus-19 (COVID-19) is commonly reported. However, these patients were not routinely referred for electrophysiological testing. Many studies reported abnormalities in nerve conduction studies (NCS) in patients who recovered from COVID-19 infection. Aim: we aimed to investigate the effect of COVID-19 infection on patients who performed NCS prior to the COVID-19 pandemic and after recovering from COVID-19 illness. Methods: A cohort retrospective study was conducted, which included males and females (average age 50.6 years old) participants who performed NCS before the pandemic and were not hospitalized during their COVID-19 illness. We assessed sensory and motor NCS for the ulnar, median, peroneal, tibial, and sural nerves. A total of 14 ulnar and median nerves and six tibial, peroneal, and sural nerves were assessed. Results: All tested parameters were normal in most of our participants. However, there was a significant increase in amplitude and decrease in conduction velocity (CV) in sensory NCS in median nerves ( p <0.005) and ulnar nerves ( p <0.05). There is an increase in amplitudes and a decrease in the CV in the lower limbs' sensory and motor NCS and the motor ulnar and median nerves, but this did not reach a significance level. Conclusion: This is the first study to assess the effect of COVID-19 on the same nerves (before and after COVID-19 infection). Although all NCS parameters were normal, the paired analysis showed that the median and ulnar sensory nerves are the most affected by COVID-19. Standardized electrodiagnostic guidelines are recommended to be established for recovered COVID-19 patients for early diagnosis of neural functions to ensure optimal recovery. This research was not funded. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.